Air cleaner



A. MARSHALL 2,134,978

AIR CLEANER 2 Sheets-Sheet 1 Filed Jan. 22, 1937 Nov. 1, 1938.

INVENTOR- #1. EXA NDE/PMRJHALL ATTORNEY 000000000 0000000000 0000060000 000000000 o00b600Ob 0600000 00 aovuooauonL 60500 605 Nov. 1, 1938. A. MARSHALL 7 AIR CLEANER Filed Jan. 22, 195 2 Sheets-Sheet 2 Fi s}:

l N V E N TO R H L EXA NDEFMfl/PJHA L 1.

ATTORNEY Patented Nov. 1, 1938 PATENT OFFICE Am CLEANER Alexander Marshall, Portland, Ores. Application in..." 22, mar, Serial No. 123.581

This invention relates to improvements in air cleaners and more particularly to the type of air cleaner shown and described in my co-pending application, filed January 24, 1936 under Serial Number 60.697, of which this application is a continuation in part. As therein pointed out. an

important object of the invention is the provision of an air cleaner which is readily adapted for use in connection with carburetors of any type of engine for cleaning air to be delivered thereto.

The invention is also readily adaptable for conditioning air to buildings, railroad cars, busses, and the like.

Another equally important object is the provision of an air cleaner of this character which through centrifugal action will emciently separate dust and foreign matter from the air and deposit such matter in a sealed container where it is held by vacuum created by certain air forces passing through the cleaner. 1

Still another object of the invention is the provision of an air cleaner which is of simple, eilicient, durable .and inexpensive construction and wherein there are no moving parts.

These and other objects will appear as my invention is more fully hereinafter described in the following specification, illustrated in the accompanying drawings and finally pointed out in the appended claims.

In the drawings:

through one form of my new and improved air cleaner.

Figure 21s a sectional plan view taken on the line 2-2 of Figure 1.

Figure 3 is a sectional plan view taken on the line 3-3 of Figure 1.

Figure 4 is a sectional view taken on the line 4-4 of Figure 2 to illustrate a series of downwardly inclined projections for imparting a swirling motion to the air entering the cleaner housing.

Figure 5 is a longitudinal sectional view of an other form of the invention.

Figure 6 is a fragmentary detail view projected from the side of Figure 5 to illustrate a clamping element.

Referring in detail to Figure 1, reference numeral i indicates a ca'sin preferably of conical shape and arranged vertica 1y with respect to the engine or apparatus to which it is applied. The upper end of the casing I is flanged outwardly as at 2 for supporting a slotted annular plate 3, which is formed with downwardly inclined projections 4, which are provided to impart a swirling Figure l is a longitudinal sectional view motion to air passing into the casing. A vertically arranged air duct 5 is supported by the plate 3 and extends therethrough and into the casing I. The lowermost end of the air duct is in spaced relation to the casing as shown. Mounted withl in the casing in spaced relation to its side walls, and also in spaced relation to the air duct, is a conical-shaped inner casing 8 which is formed with a plurality of elongated slots 1. The uppermost end oi the inner casing is in open spaced l0 relation to the outer casing and is secured thereto by suitable blocks or fastening elements 8.

An air strainer in the form of a perforated collar, screen, or the like, as indicated at 8. is superimposed upon the casing I and secured thereto by 16 any suitable means such, for instance, as the bolts iii. A cover plate Ii is provided for the uppermost end of the cleaner and is also held in place by the bolts i0.

The lowermost end of the casing I is formed 20 with a cylindrical projection I! which is sealed to the walls of the casing I, as at i3, and also sealed across its lower end by means of a disc ll. The lowermost end of the casing l is formed into a spout l5 whose open end terminates within a receptacle It. The spout I5 is sealed 'in airtight relation to the disc It. The spout is curved, as shown, so that its open end is directed toward one side of the receptacle for the purpose of breaking up the swirl of air from the casing "which would otherwise be directed to and agitate the contents of the receptacle, and in some instances would draw the contents out of the receptacle back up into the casing. The lower extremity of the cylindrical projection i2 is formed with screw threads I! for receiving the threaded end of the receptacle l6. Any suitable form of rubber gasket i8 is provided for sealing the upper end of the receptacle-with respect to the cylindrical projection. By this arrangement the receptacle and easing are sealed in air-tight relation with each other so that the reduced pressure created within the casing will be maintained within the interior of the receptacle.

The operation of the device just described is as follows. Assuming the outer end of the air duct 5 is connected by suitable pipe or manifold (not shown) with the carburetor of an engine. The reduced pressure within the air duct 5 causes air to be drawn through the screen 9. downward- 1y through the projections 4 and set into a swirling motion as it enters the upper end of the easing i. The sw rling motion of the air causes the dust and other foreign matter to be thrown to the side walls of the casing by centrifugal force and most of it remains in contact with the wall throughout its spiral passage downwardly to the spout. Those particles of dust that are thrown to the inside wall of the inner casing Q spiral around until they pass through the several slots 1 formed therein. Any particles of the dust that continue to spiral downwardly below the lowermost edges of the slots will eventually fall through the lowermost end of the inner casing 6 and into the spout it. Thus all of the dust and foreign matter which has been separated from the air is directed into the receptacle It where it is held by a reduced pressure. The reduced pressure is due to the centrifugal motion of the air which causes a low pressure area at the center of the cone. The pressure in the receptacle is reduced, due to the fact that the receptacle communicates with the conical casing through a passage adjacent to which is the above mentioned low-pressure area, air will flow from the receptacle until the pressures are equalized, the reduced pressure will thereafter be maintained in the receptacle due to the seal. After the swirling air has thrown out the dust and foreign matter it is then drawn into the duct 5 and thence into the carburetor or other apparatus to which it is attached.

The form of invention illustrated in Figure 5 is substantially the same as that shown in Figure 1 except that I superimpose a supplemental cleaner, generally indicated at I9, above the screen or perforated plate 20, and also in that I 'provide a single casing 2| instead of an inner and outer casing as previously described. The

receptacle 22 is sealed with respect to the lowermost end of the casing 2|, and also with respect to the spout 22, as previously described, so that the vacuum created. as aforesaid, within the easing will be directed to the interior of the sealed receptacle.

The supplemental cleaner ll is embraced within a housing 21 secured to the screen 2| by any approved form of clamps 2!, and consists of a dome-shaped filter 2i mounted upon a domeshaped plate 21 having a screen skirt portion 28. The plate 21 is disposed directly above'the air duct 29 so that the outgoing air will be deflected and caused to pass through more of the filter than it would if discharged directly up through the crown of the filter.

In both forms of the invention it is of utmost importance that the lower end, or spout, of the casing be in open communication with the interior of the receptacle, and that the receptacle and the casing be hermetically sealed with respect to each other so that a partial vacuum will be created and maintained within the receptacle for the purpose of trapping and holding the dust and other foreign matter within the receptacle. Any leakage of air between the casing and the receptacle would, of course, destroy the partial vacuum and would thereby defeat the purpose of the invention. I am aware that the casing and the receptacle may be hermetically sealed with respect to each other in a number of different ways and I, therefore, do not wish to be limited to the exact form of sealing shown and described. The sealing of the receptacle with respect to the casing and terminating the casing in open communication with the receptacle constitute an important feature of the invention.

Another important feature is the exact location, or disposition, of the lowermost end of the air duct 8 with respect to the inner wall. or walls, of the casing. I have found by numerous experiangers ments that the proper location of the air duct for the greatest efficiency is substantially in the position shown. These cleaners, of course, are made in a variety of sizes and in each case I have found that the proper location of the lower end of the duct with respect to the interior of the casing is approximately 80 per cent of the depth of the casing. By numerous tests I have found that raising or lowering the spout with respect to this precise location varies its degree of emciency. However, a range of adjustment of approximately %th of an inch in either direction from this position is permissible without aifeeting the efficiency of the device to any great extent.

Having thus described the invention, what I claim as new and desire to protect by Letters Patent is:

1. An air cleaner comprising a conical housing open to the atmosphere at one of its ends and its opposite end being curved and in open communication with the interior of a sealed receptacle, means for directing air in a swirling motion from the open end of the housing toward the receptacle, and means for drawing off the air after it has entered the housing.

2. In an air cleaner having a housing open to the atmosphere at one of its ends and having means at said open end for imparting a swirling motion to air entering the housing, the combination of a sealed receptacle secured to the opposite end of the housing and said housing term nating in open communication with the interior of the receptacle, and said terminal end of the housing being turned toward the wall of the receptacle.

3. An air cleaner comprising a housing open to the atmosphere atone of its ends and its opposite end in open communication with the interior of a receptacle, an air duct disposed within the open end of the housing and extending inwardly of the housing, means surrounding the air duct for directing air in a swirling motion from the open end of the housing toward the receptacle, and

means positioned within the confines of the receptacle for breaking up the air swirl in the housing and preventing the same from extending into the receptacle, said means comprising a'laterally disposed terminal end of the housing.

4. An air cleaner comprising, in combination. a conical housing open to the atmosphere at its larger end, a sealed receptacle in open communication with the smaller end of said housing for receiving dust separated from the air. means for directing air in a swirling motion from the larger end of the housing toward said receptacle. means for drawing off air after it has entered the housing, and laterally disposed means formed on the smaller end of the housing for breaking up the swirling motion of the dust thereby maintaining a relatively quiescent condition of the air in the receptacle.

5. An air cleaner comprising, in combination, a conical housing open to the atmosphere at its larger end. a sealed dust receiving receptacle having a passageway connecting the same with the smaller end of said housing, means for directing air in a swirling motion from the larger end of the housing toward said receptacle, meansfor drawing oil air after it has entered. the housing, and laterally disposed means formed on the end of said housing for breaking up the swirling motion of the dust thereby maintaining a relatively quiescent condition of the air in said receptacle.

8. An air cleaner'comprising a conical housing open to the atmosphere at one of its ends, means at the open end of the housing for directing air anddust thereinto in a swirling motion, means for drawing ofi the air after it has entered the housing and normally reversed itself and thereby created a low pressure area below said point of reversal, a sealed container in open communication with the interior of said housing adjacent said low pressure area and adapted to receive the dust discharged from the swirling air, and means for breaking up the swirling motion of the dust beyond that end of the housing in open communication withthe receptacle, said means comprising a duct extending downwardly and laterally from said housing.

'7. In an air cleaner having a housing open to the atmosphere at one of its ends and having means at said open end for imparting a swirling motion to air and dust entering the housing, the combination of a sealed receptacle secured to the opposite ends of the housing for receiving dust discharged from the swirling air, said housing terminating in open communication with the interior of the receptacle and formed with means for breaking up the swirling motion of the dust, said means comprising a substantially laterally turned end of the housing with respect to the axis of the housing.

8. In an air cleaner having a housing open to the atmosphere at one of its ends and having means at said open end for imparting a swirling motion to air and dust entering the housing, the combination of a sealed receptacle secured in open communication to the opposite end of the housing by means of a tubular interconnecting portion, said tubular connection being turned laterally relative to the axis of the housing.

9. An air cleaner comprising a casing including a conical shaped portion and a cylindrical portion communicative with one another, an air outlet communicating with the cylindrical portion and one end of the conical-shaped portion and spaced from the walls of the latter, means in the cylindrical portion forming therein an air inlet passage of spiral formation communicative with one end of the conical-shaped portion and the other end communicative with the atmosphere, a laterally extending discharge throat formed on the conical-shaped portion, means detachably connecting a container to the conical-shaped portion with the throat extending into said container, said conical-shaped portion including inner and outer walls providing inner and outer spaces both communicating with the throat and said inner wall having slots communicating with the inner and outer spaces.

ALEXANDER MARSHALL. 

